PENDULUM CROSSHAIR FOR WEAPON SIGHT
The pendulum crosshair for a weapon sight incorporates a thin, rigid wire pivotally suspended at its upper end to a point at or immediately above the peripheral end point of the fixed vertical crosshair in the reticle of a weapon sight. If the weapon, and thus the sight, is tilted or canted from the vertical when aiming, the pendulum crosshair will misalign with the fixed vertical crosshair in the sight to indicate to the shooter that the weapon is canted. This allows the shooter to correct the cant or tilt of the weapon to avoid the lateral displacement of the shot that would otherwise occur due to lateral displacement of the elevation correction for the sight line.
This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/489,905, filed May 25, 2011.
BACKGROUND OF THE INVENTION1. Field of the Invention
The present invention relates generally to sighting devices for firearms and archery bows, and particularly to a pendulum crosshair for a weapon sight to alert the marksman of an out of plumb orientation of the weapon.
2. Description of the Related Art
Virtually all weapons intended for serious hunting and/or target use include sights that are adjustable for elevation, i.e., to compensate for the drop or fall of the projectile (bullet, arrow, etc.) between the time it is fired and the time it reaches the target. As an example of the above, a bullet or round traveling at an average velocity of 2,000 feet per second to a target that is 2,000 feet away from the shooter will be accelerated downward by the force of gravity at a rate of about 32 feet per second per second, for a drop or fall of about sixteen feet over the 2,000 foot distance. Of course, arrows travel at a considerably slower speed and over shorter distances, but the principle remains the same. Accordingly, weapon sights universally have some means to compensate for this factor by angling the sight slightly downward so that the weapon is aimed slightly high when the sight is precisely on the target. Ideally, the line of sight of the scope or other sights and the parabolic arc traveled by the projectile will meet at the range of the target, or very close to that range. At relatively longer ranges, the bullet will actually tend to rise somewhat above the line of sight of the scope before dropping back below the sight line as its energy is expended.
A problem with the above is that such an elevation correction will only be absolutely accurate when the weapon is aligned vertically relative to gravity, i.e., the weapon is held in a plumb orientation. If the weapon is canted or tilted relative to the vertical, the elevation correction will be canted from the vertical accordingly. The lateral error induced will depend upon the angle of the cant of the weapon, as well as the angle subtended between the sight line and the alignment of the projectile when it is fired from the weapon (i.e., the bore of the firearm or the alignment of the arrow when released) and, of course, the distance to the target. All other things being equal, the greater the cant or tilt angle of the weapon from the vertical, the greater will be the resulting lateral error between the sight line to the target and the impact point of the projectile at the target distance.
Thus a pendulum crosshair for a weapon sight solving the aforementioned problems is desired.
SUMMARY OF THE INVENTIONThe pendulum crosshair for a weapon sight comprises a sight reticle having a pivotally movable crosshair therein, formed of a thin, rigid wire or the like. The pivoting crosshair is suspended at its upper end at or immediately above the peripheral end point for the upper end of the fixed vertical crosshair in the reticle, the pivoting crosshair being free to pivot about its attachment point. The movable pivoting crosshair acts as a pendulum, always hanging vertically within the reticle, regardless of the lateral tilt or cant of the reticle. The shooter need only orient the weapon so that the pivotally attached crosshair is directly aligned with the fixed vertical crosshair of the sight reticle to assure that the weapon is being held vertically or plumb with no lateral tilt or cant. This assures the shooter that the elevation correction is entirely in the vertical plane, and will not throw off the aim laterally due to an undesired lateral component as a result of the cant or tilt of the weapon. The device may be applied at the focal plane of a telescopic sight for a firearm, e.g., a rifle, or may be applied to the sighting mechanism of an archery bow sight or other weapon sighting system.
These and other features of the present invention will become readily apparent upon further review of the following specification and drawings.
Similar reference characters denote corresponding features consistently throughout the attached drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTSThe pendulum crosshair for a weapon sight provides the shooter with information regarding the vertical alignment of his or her weapon, thereby allowing the shooter to maintain true vertical alignment of the weapon and corresponding elevation adjustment between the sight system and the initial projectile path as defined by the firearm bore or arrow release. This is desirable in order to prevent the introduction of a lateral component to the plane defined by the sight line of the weapon sights and the parabolic path of the projectile after it has been fired. If the weapon is tilted or canted from the vertical, i.e., out of plumb, the resulting lateral offset of the sight line and projectile path will result in lateral displacement of the impact point of the projectile on the target, even when the sight line is aligned precisely with the center of the target. The pendulum crosshair is adaptable to any practicable weapon sight, including telescopic sights for firearms (rifles, etc.) and archery bow sights.
The movable pendulum crosshair 12 is of very lightweight, preferably being formed of a very thin strand of metal wire or other suitable material. The pendulum crosshair 12 preferably has a length 32 of only about half the vertical span of the sight reticle 18 as subtended by the fixed vertical crosshair 14, i.e., the pendulum crosshair 12 extends from its attachment pin 28 only to the center of the reticle 18, as defined by the intersection of the fixed vertical and horizontal crosshairs 14 and 20 and as shown in
The two archery bow sights 110 of
In the case of
It is to be understood that the present invention is not limited to the embodiments described above, but encompasses any and all embodiments within the scope of the following claims.
Claims
1. A pendulum crosshair for a weapon sight, comprising:
- a sight reticle support defining a periphery;
- a fixed vertical crosshair disposed diametrically across the sight reticle support, the fixed vertical crosshair having an upper end adjacent the periphery of the sight reticle support;
- a pendulum crosshair mount disposed at the periphery of the sight reticle support adjacent the upper end of the fixed vertical crosshair; and
- a movable crosshair pivotally suspended from the crosshair mount.
2. The pendulum crosshair for a weapon sight according to claim 1, further comprising a weapon sight, the sight reticle support being mounted in the weapon sight.
3. The pendulum crosshair for a weapon sight according to claim 2, wherein the weapon sight is a firearm telescopic sight.
4. The pendulum crosshair for a weapon sight according to claim 2, wherein the weapon sight is an archery bowsight.
5. The pendulum crosshair for a weapon sight according to claim 1, wherein the sight reticle support has a vertical span, the movable crosshair having a length substantially one-half the vertical span of the sight reticle support.
6. The pendulum crosshair for a weapon sight according to claim 1, wherein the pendulum crosshair attachment is a pin, the pendulum crosshair being suspended from the pin, the pendulum crosshair further comprising a spacer disposed on the pin between the pendulum crosshair and the periphery of the sight reticle support.
7. The pendulum crosshair for a weapon sight according to claim 1, wherein the pendulum crosshair is a thin metal wire.
8. A sight, comprising a weapon sight having a pendulum crosshair assembly, the assembly having:
- a sight reticle support mounted in the weapon sight, the sight reticle support defining a periphery;
- a fixed vertical crosshair disposed diametrically across the sight reticle support, the fixed vertical crosshair having an upper end adjacent the periphery of the sight reticle support;
- a pendulum crosshair pivot disposed adjacent the upper end of the fixed vertical crosshair and axially aligned therewith; and
- a movable crosshair pivotally suspended from the crosshair pivot.
9. The sight according to claim 8, wherein the weapon sight is a firearm telescopic sight.
10. The sight according to claim 8, wherein the weapon sight is an archery bowsight.
11. The sight according to claim 8, wherein the sight reticle support has a vertical span, the movable crosshair having a length substantially one half the vertical span of the sight reticle support.
12. The sight according to claim 8, wherein the pendulum crosshair attachment is a pin, the pendulum crosshair being suspended from the pin, the sight further comprising a spacer disposed on the pin between the pendulum crosshair and the periphery of the sight reticle support.
13. The sight according to claim 8, wherein the pendulum crosshair is a thin metal wire.
Type: Application
Filed: Apr 19, 2012
Publication Date: Nov 29, 2012
Inventor: Carl L. Lattimer (Boonsboro, MD)
Application Number: 13/451,203
International Classification: F41G 1/38 (20060101); F41G 1/00 (20060101);